In 1,252 the Islamic world was in the middle of an golden age – much like the Italian Renaissance. It was an era of free thought and intellectual liberalism. Baghdad was home to the House of Wisdom, a library which attracted a great many Catholic and Jewish scholars. The library was the largest in the world, and was the intellectual capital of the Khwarezmid Empire. Scholars worked tirelessly to translate and persevere books from across the entire world.

At this moment in history the Mongol empire was on the rise, and had just conquered a neighboring state to the Khwarezmids. Genghis Khan sent an emissary to Otrar, the capital of his new neighbor, proclaiming “I am master of the lands of the rising sun while you rule those of the setting sun. Let us conclude a firm treaty of friendship and peace.” The diplomats carrying this messages were arrested, and then a follow up caravan was beheaded. Genghis Khan took great offense and went to war with the Khwarezmid empire. In the process Baghdad was sieged and the House of Wisdom was leveled.

Nearly every book was destroyed.

Think about that for a moment. In the era before Gutenberg developed his press, books had to be meticulously copied by hand. For a book to survive someone had to care deeply about the work, and ensure that it survived to the next generation. Every book in this library had been sourced, stored, and protected for generations. Hundreds of years of human progress were lost in a few days. The golden age of the Islamic intellectual revolution was brought to an end.

Now consider the books from this era that are still in circulation today. Over the centuries they were selected time and time again to be carefully transcribed and preserved. Throughout changing political and social climates they were seen as works worth passing down to a future generation.

The next time you’re investing in a book to read ask yourself if it will still be relevant in a decade, let alone a century.